Fault complexity degree in a coal mine and the implications for risk assessment of floor water inrush

Figures & data

Figure 1. Strata and coal-bearing strata of Huaibei Coalfield.

Figure 2. Box meshing with different geometric similarity ratios.

Table 1. E And fault-induced water inrush points of the Taoyuan coal mine.

Fault-induced water inrush point	Flow rate at water inrush points (m^3/h)	E
Panel 1018	45	0.0336
Panel 1042	15	0.0199
Panel 1066	35	0.0312
Panel II1028	40	0.0282

Figure 3. The FCI contour map.

Figure 4. Zonation of the fault complexity degree.

Table 2. Statistic of fault-induced water inrush points and Ds values.

Reference/Box scale/box meshing level	Fault-induced water inrush point	Water inrush rate (m^3/h)	Ds
Taoyuan coal mine (this study)/500m $\times$500m/$r_4=1/32r_0$	Panel 1018	45	1.31
	Panel 1042	15	1.01
	Panel 1066	35	1.39
	Panel II1028	40	1.22
Pingdingshan #2 coal mine (Li et al. 2017)/ 400m $\times \hspace{0.17em}\hspace{0.17em}$400m/ $r_3=1/8r_0$	Panel Ji 17-131	333	1.525
	−86 m drainage roadway	30	1.032
	Geng 20 track downdip	30	0.942
	Geng 20-212 return airway	90	1.272
	Track downdip	170	1.404
	−130 drainage roadway	413	1.656
	−130 drainage roadway −70.5 level	120	1.301
	Ji 15-22150 coal working surface	265.5	1.491
	Geng 20-22130 mechanical roadway	30	1.21
Liangzhuang coal mine (Shi et al. 2015)/500m $\times$500m/-	Panel 51101 W	772.2	1.6
Chensilou coal mine (Li et al. 2011)/500m $\times$500m/$r_3=1/8r_0$	Beijiao roadway	860	1.251
	Panel 2002	207	1.161
	Danjiao roadway	35	1.111
	Panel 2301	383	1.208
	Panel 21301	205	1.178
	Panel 7107	60	1.510
	branching fault of F11	15	1.233
Zhaojiazhai coal mine (Zhou et al. 2017)/500m $\times$500m/$r_4=1/16r_0$	11wind uphill	367	1.25
	11transport uphill	18	1.05
	12205 down vice-roadway	78.31	1.15
	12201 down vice-roadway	1310	1.4

Table 3. Relationship between the meshing level and Ds.

Meshing level	r	$\lg (r)$	$\lg N(r)$	Ds
1	$r_0$=500	2.6990	0.0000	–
2	$r_1$=1/2$r_0$	2.3979	0.6021	2.00
3	$r_2$=1/4$r_0$	2.0986	1.0792	1.80
4	$r_3$=1/8$r_0$	1.7959	1.4624	1.61
5	$r_4$=1/16$r_0$	1.5085	1.7853	1.49
6	$r_5$=1/32$r_0$	1.2075	2.2405	1.45
7	$r_6$=1/64$r_0$	0.9065	2.6274	1.42
8	$r_7$=1/128$r_0$	0.6054	3.0839	1.42
9	$r_8$=1/256$r_0$	0.3044	3.5427	1.42

Figure 5. In Taoyuan coal mine.

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Data availability statement

Partial of the data related to the paper are confidential.